The present invention relates generally to a garage door operator and, in particular, to an automatic garage door closer having a safety sensor for determining whether there is any activity within the garage, particularly a running vehicle, and further having, upon the absence of such activity, a programmable and pre-determined timer and command for the closing of the door.
Remote controlled door operators have become the staple use in residences, parking areas and other locations to which controlled access is deemed essential or desirable. Typically, the remote door operator includes, in addition to the mechanical components of the door and the door mounting system, a motor which is capable of driving the door between an open and a closed position, and a motor controller adapted to be connected to a power supply and which is operatively associated with the motor for controlling the movements of the door in response to various signals. In addition, the typical door operator system comprises a low power, limited range radio transmitter having a pushbutton which is actuable to produce a coded signal, and a radio receiver/decoder for triggering operation of the controller when the coded signal is received in the proper format. This xe2x80x9cremotexe2x80x9d avoids the need for the driver to get out of the car to open and close the door in the case of a garage and the like. In addition to the transmitter, such a system also includes a manual wall switch to control the movement of the door.
Although the majority of the problems associated with such a door operating system occur with the remote operator, any damage done, or other essential safety issues, are typically associated with the movement of the door. For example, when a door operator is commanded to close, the door operator may close onto an obstacle in the way of the door which causes damage to the operator. More importantly, the door operator also may close on an object which may be damaged such as an automobile, child""s bicycle or even (most particularly), upon a person or child.
With more instances of injury, more laws with regard thereto have been proliferated by the local, state and federal legislate. For example, effective as of Jan. 1, 1993, a law was placed into effect that all electronic garage doors installed must be equipped with a safety device that will reverse a closing door if an obstruction is present in the last six inches of the door""s travel, or six inches above ground level. In order to comply with this law, among others, automatic garage door operator manufacturers have incorporated many different safety features. The two such features most incorporated include edge sensors and light beam sensors.
Edge type sensors usually comprise a flexible strip attached to the bottom edge of the garage door, which flexible strip deforms when it comes in contact with an obstacle. Deformation of the flexible strip may increase pressure of a trapped fluid within the strip or close switches signaling the garage door operator that an obstacle has been encountered. The garage door operator then switches into its up mode and immediately raises the garage door. Edge sensors thus provide an open-circuit when no obstruction is sensed and provide an closed-circuit when an obstruction contacts the sensor. This type of sensor is not entirely adequate not only because of its relatively high cost, but more importantly, because once a force was exerted in the opposite direction, a sufficient pressure may have already been exerted against the object to cause damage. For example, if a small child were in the path of the garage door, the child could be knocked down and injured prior to the garage door reversing direction.
On the other hand, light sensors typically include infrared transmitters and receivers hard wired to the motor so that if an obstacle is located between the transmitter and receiver, which necessarily means in the path of the garage door, the receiver would send a signal to a motor controller to reverse direction of the garage door. In other words, the transmitter produces a light beam that is aligned so that it extends across the doorway and strikes the receiver on the other side. As long as the receiver detects the light beam, the receiver outputs a low level signal. When the light beam is broken and the receiver does not detect the presence of the light beam, the sensor outputs a high-level signal indicating the presence of an obstruction in the doorway.
Although these two features may provide for the safety of objects in the path of the garage door, they cannot determine whether there is any activity within the garage, particularly a running vehicle, at the time of door closing. Such a feature is needed when the garage door operating system includes an automatic closer such as that disclosed within U.S. Pat. No. 4,463,292, incorporated herein by reference. Such a system typically includes a security timer for door closure after a predetermined period of time. This automatic closing feature solves the problem of the occasional left open door, or a door that has been opened by stray radio frequency signals. Without the automatic closure, an open door will provide access for intruders to the garage and make it easier for a burglar to break into a door leading from the garage to the house.
However, with this automatic closure comes additional safety problems. Animals, including family pets, people and even small children may get trapped in the garage after the automatic closure. If trapped therein, they may be subjected to extreme heat or extreme cold, trapped gases or even exhaust fumes from a running automobile. The present invention provides for safety features that will determine whether there is any activity in the garage, particularly a running vehicle, before the automatic closure of the door. If desired, the present invention may be combined with the previously discussed edge and/or light sensors to provide for the safest garage door operating system as possible.
Accordingly, it is a general object of the present invention to provide for an improved garage door operator.
It is another general object of the present invention to provide for an automatic garage door closer system.
It is a more specific object of the present invention to provide for a garage door operator having an automatic garage door closer including a safety sensor for determining whether any activity is present within the garage.
Still another more specific object of the present invention is to provide for a garage door operator having an automatic garage door closer including a safety sensor for determining whether an automobile is running within the garage.
According to the present invention, there is provided a garage door operator having a control unit connected to command the motor to open and close the door. An auto closure module including a timing unit counts down a predetermined period of time for which the door will remain in an opened position before the automatic closure thereof. An activity detector is included for determining whether any activity is present within the garage during the countdown period, and upon activity detection, the auto closure module is disabled.